2006 年 17 巻 4 号 p. 423-426
Low-molecular-weight selenocompounds without selenol groups, N-methyl, N-phenyl-(2-selenomethyl)benzoylamide, N-phenyl-(2-selenoallyl)benzoylamide, N-phenyl-(2-selenopropyl)benzoylamide, and bis[1-methyl-2-(N-phenylcarboxamido)ethyl] diselenide, dibenzyl diselenide, were synthesized and their antioxidant activities were evaluated. Among the synthesized selenocompounds, N-phenyl-(2-selenoallyl)benzoylamide had the highest glutathione peroxidase(GPx)-like activity, and the activity increased depending on the concentration. The activity of N-phenyl-(2-selenoallyl)benzoylamide was several times higher than that of selenomethionine, though it was about 1/10 of ebselen. These results suggest that selenocompounds which don't have selenol groups can also behave as a GPx-like reductant, where a different reaction mechanism from that for selenocompounds with selenol groups is present. Spectrophotometric studies also supported this suggestion. It may be possible that selenium atom located between two carbon atoms in the molecule is oxidized to selenoxide by an oxidant and then selenoxide is reduced to selenium by reduced form of gluta-thione, thus GPx-like reduction of hydrogen peroxide by selenocompounds without selenol groups occurs. N-phenyl-(2-selenoallyl)benzoylamide had superoxide anion scavenging activity, although it was comparatively low. These results indicated that selenocompounds without selenol groups such as N-phenyl-(2-selenoallyl)benzoylamide can be reductants against peroxide or other oxidant species possibly by forming selenoxide, though their antioxidant activity may not be high.
